Cardboard package of orthogonal prismatic shape



March 24, 1970 l. T. VIRROS 3,502,257

CARDBOARD PACKAGE OF ORTHOGONAL PRISMATIC SHAPE Filed July 12, 1968 5 17 -3 4 i 2/ -l I I ig 3 fl A 5 Q 1 V k v H -6 United States Patent U.S. Cl. 229-51 3 Claims ABSTRACT OF THE DISCLOSURE An improvement in a cardboard package of orthogonal prismatic shape, rnost appropriately a coifee package, which has been shaped from a plane blank by folding the blank to form a tube with a rectangular cross section and by forming alongside one of the edges a glued joint holding the tube together, in which the longitudinal edges of the cardboard overlap, and by closing the ends of the tube, whereat on the package a transversal, tear-oft zone has been formed which is bounded both on the inside and on the outside by two weakening lines, the inside weakening lines being located between the outside weakening lines, and whereat the tear-off zone has been cut oif by means of a straight cut longitudinal to the package. The invention is characterized in that for the purpose of forming a gaping cut, the cut has been placed in the side of the package adjacent the glued jointclose to the common edge of these sides but spaced in entirety from this edge.

When a cardboard package is opened in the household, certain difliculties are encountered, and for this reason various proposals have been made in order to facilitate the opening procedure. One of the most appropriate means to achieve this is that in which in the package a transversal, tear-ofl? region has been provided which has for its boundaries both on the inside and on the outside two weakening lines, the inner weakening lines being located between the outer ones, and the tear-otf zone having been cut off by means of a straight cut in the longitudinal direction of the package. In this known package, the cut is located exactly at the edge. In that case the cut does not gape, as a result of which it is difficult to grasp with the fingers.

The aim of the present invention is to afford an improvement of such previously known packages so that it will be easier to tear 01f the tear-01f zone. A cardboard package according to the invention is characterized in that, for the purpose of forming a gaping cut, the cut is positioned on the side adjacent to the glued joint close to the common edge of these two sides but spaced in entirety from this edge. It is thus to be understood that in the invention use is made of the phenomenon that the assembled cardboard package is in a condition of stress close to the edge. When the tear-off zone has been cut off, according to the invention, at this point which is under stress a gaping cut is achieved which is easy to grasp with the fingers. By placing the cut on the particular side which is adjacent to the side with the glued joint and close to the common edge of these sides, good purchase or leverage aiforded by the glued joint is obtained. More- 3,502,257 Patented Mar. 24, 1970 over, the tearing of the package in two then begins at the glued joint, where the resistance against tearing is greatest.

The invention is described in detail in the following description with reference to the appended drawing, in which FIG. 1 shows the completed cardboard package, in perspective,

FIG. 2 is a section taken along the line II--II in FIGrl,

FIG. 3 is a section taken along the line III-III in FIG. 1, and

FIG. 4 is a section taken along the line IV-IV in FIG. 1.

The package is formed from a plane blank by folding the blank to form a tube of rectangular cross section. Alongside one of the edges a glued joint 1 holding the tube together is formed, in which the longitudinal edges of the cardboard overlap. The ends of the package are closed in conventional manner.

On the package a transversal, tear-otf zone 2 has been formed. The zone is bounded on the inside by two weakening lines 3. On the outside the zone is likewise bounded by two weakening lines 4. The inside weakening lines 3 are located between the outside weakening lines 4. A zone bounded by such weakening lines is very easy to tear oil from the package. In the arrangement illustrated in the drawings, cuts 7 piercing through the upper cardboard layer have been made at the glued joint 1 along the continuations of the outside weakening lines, as can best be seen from FIG. 4.

The tear-off zone 2 has been cut off by means of a cut 5, which is longitudinal to the package and which is located on the side adjacent to the side with the glued joint close to the common edge of these sides, as can best be seen from FIG. 3. The distance of the cut 5 from the edge adjacent to it is less than 1 mm. In the drawing this distance has been considerably exaggerated for the sake of clarity.

A package according to the invention is opened in that one grasps with the finger or fingernail the tongue '6 protruding beside the cut 5 and tears the zone 2 completely off the package. The package is then broken in two.

What is claimed is:

1. A cardboard package of orthogonal prismatic shape formed by folding a plane blank to produce a tube of a rectangular cross-section with overlapping longitudinal edges which are adhesively joined together to form a glued joint holding the tube together, the ends of the tube being closed, a transverse, tear-off section in said tube bounded both on the inside surface and on the outside surface of the tube by two weakening lines formed directly in said tube, the weakening lines on the inside surface being located between the weakening lines on the outside surface, and a straight longitudinal cut in said tear-off section extending through the blank between the weakening lines on the outer surface, an improvement wherein said cut is placed in the side of the package adjacent the glued joint proximate the corner of the joint but spaced in entirety from said corner, whereby the cut gapes under the stress at said corner thus facilitating eugagement of the tear-off section thereat to commence tearing of the tear-01f section.

' 3,502,257 3 4 2. An improvement as claimed in claim 1 wherein cuts References Cited are formed in the outer overlapping edge of the blank at said joint, the latter cuts extending completely through UNITED STATES PATENTS the outer overlapping edge and being aligned with the 2,608,341 8/1952 Ec kn 1an 5 weakening lines in the outer surface of the inner over- 2,626,096 1/1953 Hlckln 229-51 lapping edge 5 2,7 6,076 4/1955 Guyer 229-51 3. An improvement as claimed in claim 1 wherein a 3,189,187 6/1965 Guyer et -5 tongue is formed on the inner of the overlapping edges of the blank between said corner of the joint and said cut DAVID BOCKENEK Pnmary Exammer in the tear-off section; said tongue being engageable to 10 commence tearing of the tear-oil section. 

